Schalk came through the youth ranks of NAC Breda, earning the nickname of Der Bomber of Breda because of his reputation as a footballer with remarkable goalscoring instincts, comparable to legendary German striker Gerd Müller. On 1 May 2011, Schalk made his senior debut for NAC against Heracles Almelo in the 33d round of the 2010–11 Eredivisie season.

On 9 August 2011, Schalk agreed a new two-year contract at NAC until June 2013.

After losing any perspective on playing matches for NAC Breda, Schalk was sent on loan to PSV, where he played for Eerste Divisie side Jong PSV. He scored 6 times in 16 matches for the Eerste Divisie side. On 28 June 2014, Schalk signed a one-year deal with Eredivisie side Go Ahead Eagles on a free transfer.